travis config, license and readme

.travis.yml

+language: android
+android:
+  components:
+    # The BuildTools version used by your project (make sure it's exactly the same as in the build.gradle)
+    - build-tools-29.0.3
+    # The SDK version used to compile your project
+    - android-29
+    # The SDK version used by the system image
+    - android-22
+    # The system image, to run an emulator during the tests
+    - sys-img-armeabi-v7a-android-22
+before_script:
+  # Emulator Management: Create, Start and Wait
+  - echo no | android create avd --force -n test -t android-22 --abi armeabi-v7a
+  - emulator -avd test -no-audio -no-window &
+  - android-wait-for-emulator
+  - adb shell input keyevent 82
+

README.md

+# PixelDroid
+Software Development Project course, EPFL, Spring 2020